This one works best if you have a hand blender to make the vinaigratte, but a mortar/pestle and a way to shake things up might work just as well. Or a food processor or big blender.

Ingredients

Veggies3 small beets, peeled and sliced into 1/4 t 1/8 inch rounds1 small to medium sweet potato, also peeled and sliced into 1/4 to 1/8 inch rounds1 8 oz bag of baby spinacha few sprigs of fresh rosemary, chopped up into small bits.

Dressing (all measurements approximate)~2 tbsp olive oil~3 tbsp balsamic vinegar2 medium sized pitted prunes, sliced/smashed. ("Plum vinaigrette" sounds better than "Prune vinaigrette", but I used prunes)juice from 1/4 of a lemon~1 tsp sugar1 tsp garlic paste (the kind that comes in a tube; I used about a 1/2 inch squeezed out of the tube)

Directions:

Preheat oven to 400F.

Put all of the vinaigrette ingredients into the blender (or into the cup for the hand blender) and blend until smooth. Adjust any flavors to taste.

Pour the vinaigrette into the glass dish and add the beet and sweet potato rounds, tossing to coat. Arrange them in overlapping rows in the dish, sprinkle with rosemary, and bake for 35 to 45 minutes until they are soft and look done.

When done baking, heat a small bit of water in the frying pan on medium. Add the baby spinach straight from the bag, and put the lid on to wilt it for a minute or two.

Serve beets/potatoes on the spinach. If you want, transfer the beets/potatoes to a serving dish and deglaze the dish with a little bit of water to add to the spinach. But it's good just with the spinach plain/wilted and scooping up the glaze with the beets/potatoes too.